classic snow goggles with timeless design. the ashbury blackbird goggles come with a classic, timeless design. the flexible frame makes these snow goggles one of the most comfortable in the ashbury collection.an interchangeable lens for poor light conditions ensures visibility on cloudy days.dark smoke lensfor sunny and only slightly cloudy days.transmittance of visible light: 17 %yellow lensfor very cloudy days.transmittance of visible light: 54 %